Sheet Material End Detection Mechanism, Roll Body, and Method for Producing Roll Body

ABSTRACT

Provided is a sheet material end detection mechanism including: a sheet material information part indicating information on a sheet material wound around a core member in which a light passing part is formed; a reader configured to optically read the sheet material information part; and a detection unit configured to detect that the sheet material is used up. A forming part is attached to an outer surface of the core member and an inner surface of the sheet material. The sheet material information part is formed in a portion of the forming part corresponding to the light passing part. The detection unit detects that the sheet material is present when a read signal of the sheet material information part read by the reader is received and that the sheet material is used up when the read signal disappears.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to Japanese Patent Application No. 2015-080149, the disclosure of which is incorporated herein by reference in its entirety.

FIELD

The present invention relates to a sheet material end detection mechanism used, for example, for a sheet-using device that withdraws a sheet material from a roll body for use, the roll body, and to a method for producing the roll body.

BACKGROUND

Examples of the sheet-using device include a medicine packaging device that obtains information on the sheet material and operates based on this information. The information on the sheet material is provided in a core member around which the sheet material is wound (see Patent Literature 1, for example).

Conventionally, in such a medicine packaging device, a configuration for detecting that the sheet material is used up is provided separately from the configuration for obtaining the information on the sheet material. Patent Literature 1 employs a mechanical configuration using a “paper end detection pin”. In the case where such a mechanical configuration is separately provided, malfunction may possibly occur due to wear of parts or the like.

CITATION LIST Patent Literature

Patent Literature 1: JP 2009-227469 A

SUMMARY Technical Problem

It is therefore an object of the present invention to provide a sheet material end detection mechanism, a roll body, and a method for producing the roll body, which enable convenient detection of using up of the sheet material.

Solution to Problem

The present invention is a sheet material end detection mechanism including: a roll body constituted by winding a sheet material around a tubular core member; a holding unit configured to hold the roll body so as to allow the sheet material to be withdrawn; a sheet material information part provided in the roll body and indicating information on the sheet material; a reader configured to optically read the sheet material information part of the roll body held by the holding unit; and a detection unit configured to detect that the sheet material is used up based on results of the reading by the reader, wherein the core member has a light passing part through which light passes so as to enable the optical reading by the reader from inside to outside, the roll body has a forming part located between an outer surface of the core member and an inner surface of the sheet material and used for forming the sheet material information part, the sheet material information part is formed in a portion of the forming part corresponding to the light passing part, the forming part is attached to the core member and the sheet material, adhesive force between the sheet material and the forming part is larger than adhesive force between the core member and the forming part, and the detection unit is configured to detect that the sheet material is present when a read signal of the sheet material information part read by the reader is received and that the sheet material is used up when the read signal disappears, during the withdrawing action to withdraw the sheet material from the roll body held by the holding unit.

Further, the present invention is a roll body including: a tubular core member; a sheet material wound around the core member; and a forming part located between an outer surface of the core member and an inner surface of the sheet material and used for forming a sheet material information part indicating information on the sheet material, wherein the core member has a light passing part through which light passes so as to enable optical reading from inside to outside, the sheet material information part is formed in a portion of the forming part corresponding to the light passing part, the forming part is attached to the core member and the sheet material, and adhesive force between the sheet material and the forming part is larger than adhesive force between the core member and the forming part.

Further, the present invention is a method for producing a roll body by winding a sheet material around a tubular core member, the core member having a light passing part through which light passes so as to enable optical reading from inside to outside, the method including: a step of forming a sheet material information part indicating information on the sheet material, on a forming part used for forming the sheet material information part; a step of attaching the forming part onto an outer surface of the core member so that the sheet material information part corresponds to the light passing part; a step of attaching the forming part to a winding start portion of the sheet material with adhesive force larger than adhesive force between the core member and the forming part; and a step of winding the sheet material around the core member.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a perspective view simply showing a mechanism for packaging medicine using a roll body according to an embodiment of the present invention.

FIG. 2A is a perspective view showing the appearance of a roll body according to an embodiment of the present invention.

FIG. 2B is an enlarged perspective view showing a main part of the radial cross section of a roll body according to an embodiment of the present invention.

FIG. 3A is a side view showing a seal according to an embodiment of the present invention.

FIG. 3B is a bottom view showing a seal according to an embodiment of the present invention.

FIG. 4A is a schematic view in the axial direction showing a procedure for producing a roll body according to an embodiment of the present invention, where the seal is exaggerated in the thickness direction.

FIG. 4B is a schematic view in the axial direction showing a procedure for producing a roll body according to an embodiment of the present invention, where the seal is exaggerated in the thickness direction.

FIG. 4C is a schematic view in the axial direction showing a procedure for producing a roll body according to an embodiment of the present invention, where the seal is exaggerated in the thickness direction.

FIG. 5A is a schematic perspective view showing the relationship between a roll body according to an embodiment of the present invention and a holding unit of a medicine packaging machine.

FIG. 5B is a schematic perspective view showing a packaging material taken away from a core member.

DESCRIPTION OF EMBODIMENT

The present invention will be described below with reference to an embodiment. FIG. 1 is a view showing peripheral portions of a roll body 1 in a medicine packaging device including a packaging material end detection mechanism. The roll body 1 is constituted by winding a packaging material 12 that is an elongated sheet material around a core member 11. The medicine packaging device that is a sheet-using device is used by withdrawing the packaging material 12 from the roll body 1. The medicine packaging device is used for packaging solid medicine.

The medicine packaging device includes: a holding unit 2 configured to hold the roll body 1 so as to allow the packaging material 12 to be withdrawn; a hopper 4 configured to put medicine into the packaging material 12 withdrawn from the roll body 1 held by the holding unit 2; a sealing unit 5 configured to seal the medicine put into the packaging material 12 via the hopper 4 within the packaging material 12; and a control unit 7 configured to control the sealing unit 5.

As shown in FIG. 5A, the holding unit 2 has a shaft 21. The shaft 21 is provided rotatably about the axis of the shaft 21. The core member 11 of the roll body 1 is externally fitted to the shaft 21 of the holding unit 2.

A half folding mechanism 3 is provided between the holding unit 2 and the hopper 4. The half folding mechanism 3 folds the packaging material 12 withdrawn from the roll body 1 in half in the width direction. As shown in FIG. 1, the hopper 4 is inserted into the half-folded portion of the packaging material 12.

The sealing unit 5 functions as an action unit that acts on the packaging material 12 withdrawn from the roll body 1 held by the holding unit 2. The sealing unit 5 seals medicine within the half-folded packaging material 12 by thermocompression bonding of the packaging material 12. That is, the action of the sealing unit 5 serving as the action unit is exerted onto the packaging material 12 and is sealing of the packaging material 12 by thermocompression bonding.

FIG. 2A and FIG. 2B are views for explaining the roll body 1, where FIG. 2A is a perspective view showing the appearance of the roll body 1, and FIG. 2B is a perspective view showing a main part of the radial cross section of the roll body 1. The roll body 1 includes: the core member 11; the packaging material 12 wound around the core member 11; and the seal 13 located between the outer surface of the core member 11 and the inner surface of the packaging material 12 and serving as a forming part used for forming a packaging material information part 14, which will be described later.

The core member 11 is tubular and is cylindrical in this embodiment. The core member 11 of this embodiment is made of resin. However, the material of the core member 11 is not limited to resin. The core member 11 can be formed using various materials as long as it can be formed to have shape retention properties that allow the packaging material 12 to be wound therearound.

The core member 11 has a light passing part through which light passes so as to enable optical reading by a reader 6, which will be described below, from inside to outside. In this embodiment, a through window 111 serving as the light passing part is formed in the core member 11. The through window 111 is a through hole passing through the core member 11 in a direction intersecting the axis of the core member 11. In this embodiment, the through window 111 is formed to pass through the core member 11 in the inward-outward direction, that is, in the radial direction of the core member 11. The through window 111 is, for example, rectangular or square, as viewed in the radial direction. However, the shape of the through window 111 is not limited to the rectangular or square shape, and can be various shapes such as circular and polygonal shapes. As shown in FIG. 2B, the through window 111 is formed in a portion close to one end in the axial direction of the core member 11.

It is desirable that the through window 111 be formed to be as small as possible as compared with the total area of the inner surface 112 of the core member 11 (see FIG. 2B). The influence of the through window 111 on the packaging material 12 can be reduced by reducing the area of the through window 111. Specifically, the occurrence of recesses in a portion corresponding to the through window 111 in the packaging material 12 wound around the core member 11 can be reduced by the degree of the reduction in area of the through window 111. Therefore, the occurrence of wrinkles or traces of the through window 111 in the packaging material 12 can be reduced.

However, the through window 111 of this embodiment needs to have a larger area than the packaging material information part 14, which will be described below, as a sheet material information part so that the packaging material information part 14 is not hidden by the core member 11.

In the roll body 1, the packaging material information part 14 indicating information on the packaging material 12 is formed. Examples of the information on the packaging material 12 include the type of the packaging material 12 (such as material and thickness). Further, examples of the information on the packaging material 12 include information on traceability, such as information on the production lot number and factory of the packaging material 12.

The packaging material information part 14 is optically readable. The light used for optically reading the packaging material information part 14 is not limited to visible light and may be infrared rays or ultraviolet rays, for example. The packaging material information part 14 is formed by printing.

The packaging material information part 14 physically (optically or visually) integrates a plurality of elements into one. The packaging material information part 14 indicates the information on the packaging material 12 by the entirety of the packaging material information part 14 (that is, a unit of the plurality of elements). The packaging material information part 14 is formed by coding the information on the packaging material 12. In this embodiment, a two-dimensional code (“QR code” which is a registered trademark in Japan) is used as the packaging material information part 14. Accordingly, a general-purpose device can be used as the reader 6, which will be described below.

FIG. 3A and FIG. 3B are views for explaining the seal, where FIG. 3A is a side view, and FIG. 3B is a bottom view. The seal 13 serving as the forming part for forming the packaging material information part 14 is provided between the outer surface of the core member 11 and the inner surface of the packaging material 12.

The seal 13 is attached to the core member 11 and the packaging material 12 (by adhesion, sticking, or the like). At this time, the adhesive force between the packaging material 12 and the seal 13 is larger than the adhesive force between the core member 11 and the seal 13. In other words, the seal 13 is formed so that the adhesive force between the packaging material 12 and an outer surface 13 b of the seal 13 is larger than the adhesive force between the core member 11 and an inner surface 13 a of the seal 13, when being attached. The difference in adhesive force between the inner surface 13 a and the outer surface 13 b of the seal 13 can be made, for example, by making a difference in type, concentration, coating amount, or coating density, of attaching means (such as an adhesive and a pressure-sensitive adhesive) for exerting the adhesive force or reaction time for exerting the adhesive force between the inner and outer surfaces 13 a and 13 b.

The packaging material information part 14 is formed in a portion of the seal 13 corresponding to the through window 111. Specifically, as shown in FIG. 2B and FIG. 3B, the packaging material information part 14 is formed on the inner surface 13 a of the seal 13 (the inner surface when being attached to the core member 11) in a portion corresponding to the through window 111 when being attached thereto (specifically, a portion where the packaging material information part 14 can be seen through the through window 111, as seen from the inside of the core member 11).

FIG. 4A to FIG. 4C are views for explaining the procedure for producing the roll body 1. When producing the roll body 1, the packaging material information part 14 is first formed on the seal 13 by printing. Thereafter, as shown in FIG. 4B, the seal 13 on which the packaging material information part 14 is formed is attached onto the outer surface of the core member 11 (FIG. 4A). At this time, the seal 13 is attached onto the outer surface of the core member 11 so that the packaging material information part 14 corresponds to the through window 111. Next, as shown in FIG. 4C, the packaging material 12 is wound around the core member 11. At this time, the seal 13 (the outer surface 13 b) is attached to the winding start portion of the packaging material 12 with adhesive force larger than the adhesive force between the core member 11 and the seal 13 (the inner surface 13 a).

The method for producing the roll body 1 by these steps can facilitate the operation of forming the packaging material information part 14 on the seal 13 and the operation of aligning the packaging material information part 14 with the through window 111. Further, the packaging material 12 can be temporarily fixed to the core member 11, and thus the packaging material 12 can be smoothly wound around the core member 11.

FIG. 5A is a schematic perspective view showing the relationship between the roll body 1 and the holding unit 2. Though not shown in the figure, an engaged part is provided in the core member 11, and an engaging part configured to engage the engaged part of the core member 11 is provided in the shaft 21 of the holding unit 2. When the core member 11 of the roll body 1 is externally fitted to the shaft 21, the engaging part of the shaft 21 engages the engaged part of the core member 11. Accordingly, the core member 11 rotates together with the shaft 21.

The reader 6 configured to optically read the packaging material information part 14 of the roll body 1 held by the holding unit 2 is provided in the shaft 21 of the holding unit 2. The reader 6 is arranged inside the core member 11 of the roll body 1 held by the holding unit 2 and is provided so as to correspond to the packaging material information part 14 of the roll body 1.

The reader 6 is connected to a detection unit 8 configured to detect that the packaging material 12 is used up. In this embodiment, the control unit 7 and the detection unit 8 are integrally provided. However, there is no limitation to this configuration, and the control unit 7 and the detection unit 8 can be provided separately from each other.

The control unit 7 sets the temperature of thermocompression bonding by the sealing unit 5 based on the results of reading by the reader 6. Thereby, thermocompression bonding of the packaging material 12 can be performed at a temperature corresponding to the type of the packaging material 12. Further, the detection unit 8 detects that the packaging material 12 is used up based on the results of reading by the reader 6. Specifically, the detection unit 8 detects that the packaging material 12 is present when a read signal of the packaging material information part 14 read by the reader 6 is received during the withdrawing action to withdraw the packaging material 12 from the roll body 1 held by the holding unit 2. Further, the detection unit 8 is configured to detect that the packaging material 12 is used up when the read signal disappears.

When the roll body 1 is mounted on the holding unit 2, the reader 6 reads the packaging material information part 14 of the roll body 1. The control unit 7 sets the temperature of thermocompression bonding by the sealing unit 5 based on the results of reading by the reader 6. The packaging material 12 is withdrawn from the roll body 1 and is folded in half by the half folding mechanism 3 in the case where the half folding mechanism 3 is provided. Medicine is put into the half-folded portion of the packaging material 12 via the hopper 4. The medicine is sealed within the packaging material 12 by the sealing unit 5. At this time, the sealing unit 5 performs thermocompression bonding of the packaging material 12 at the temperature of thermocompression bonding set by the control unit 7. The medicine packaging device repeats the aforementioned operations of putting and sealing of the medicine while withdrawing the packaging material 12 from the roll body 1.

FIG. 5B is a schematic perspective view showing the packaging material 12 taken away from the core member 11. As the packaging material 12 is withdrawn from the roll body 1, the end of the packaging material 12 wound around the core member 11 is also withdrawn finally. The adhesive force between the packaging material 12 and the seal 13 is larger than the adhesive force between the core member 11 and the seal 13. Therefore, as shown in FIG. 5B, the seal 13 on which the packaging material information part 14 is formed is also taken away from the core member 11 together with the packaging material 12. Then, the packaging material information part 14 is displaced from the position corresponding to the through window 111 of the core member 11. Therefore, the reader 6 cannot read the packaging material information part 14 anymore. The detection unit 8 detects that the packaging material 12 is used up by the fact that the reader 6 cannot read the packaging material information part 14.

Thus, the packaging material end detection mechanism is constituted by the roll body 1, the holding unit 2, the packaging material information part 14, the reader 6, and the detection unit 8.

According to this embodiment configured as above, the roll body 1 is located between the outer surface of the core member 11 and the inner surface of the packaging material 12. The roll body 1 has the seal 13 used for forming the packaging material information part 14, and the packaging material information part 14 is formed in the portion of the seal 13 corresponding to the through window 111. The reader 6 is provided so as to correspond to the packaging material information part 14. Accordingly, the reader 6 can read the packaging material information part 14 until immediately before the packaging material 12 is used up. Then, the control unit 7 can suitably control the sealing part 5.

Further, the seal 13 is attached to the core member 11 and the packaging material 12. Thus, since the seal 13 is attached also to the core member 11, the operation of aligning the through window 111 of the core member 11 with the seal 13 can be facilitated.

Moreover, the adhesive force between the packaging material 12 and the seal 13 is larger than the adhesive force between the core member 11 and the seal 13. Therefore, as the packaging material 12 is withdrawn from the roll body 1, the seal 13 on which the packaging material information part 14 is formed is finally taken away from the core member 11 together with the packaging material 12. Then, the packaging material information part 14 is displaced from the position corresponding to the through window 111. Then, the reader 6 cannot read the packaging material information part 14 anymore.

Based on this point, the detection unit 8 is configured to detect that the packaging material 12 is present when a read signal of the packaging material information part 14 read by the reader 6 is received during the withdrawing action to withdraw the packaging material 12 from the roll body 1 held by the holding unit 2. Further, the detection unit 8 is configured to detect that the packaging material 12 is used up when the read signal disappears. Thus, the detection unit 8 can detect that the packaging material 12 is used up by the fact that the reader 6 cannot read the packaging material information part 14. Accordingly, there is no need to provide a mechanical configuration for detecting that the packaging material 12 is used up (such as the “paper end detection pin” according to Patent Literature 1). Therefore, parts where malfunction may possibly occur can be reduced, and therefore a packaging material end detection mechanism in which malfunction is less likely to occur can be provided.

Hereinbefore, an embodiment of the present invention has been described. However, the present invention is not limited to the aforementioned embodiment, and various modifications can be made without departing from the gist of the present invention.

The roll body 1 may be constituted by winding the packaging material 12 that has been folded in half in advance around the core member 11. In this case, the half folding mechanism 3 provided between the holding unit 2 and the hopper 4 in the aforementioned embodiment is not needed.

As the packaging material information part 14, codes other than the two-dimensional code may be used. As the packaging material information part 14, a barcode (one-dimensional code) may be used, for example.

Various means can be employed as the packaging material information part 14 as long as it is optically readable. The packaging material information part 14 may include characters, graphics, or symbols as its components. The packaging material information part 14 may include color elements as its components. The packaging material information part 14 may include projections and recesses as its components. Further, the packaging material information part 14 may be constituted by a plurality of elements that are physically (optically or visually) separated from each other.

As the method for forming the packaging material information part 14, methods other than printing may be used. As the method for forming the packaging material information part 14, various methods that do not fall within the concept of printing such as vapor deposition and etching can be employed as long as the methods allow the packaging material information part 14 that is optically readable to be formed.

A fitting member may be fitted in the space of the through window 111 that is a through hole. The fitting member is made of a material through which light passes, thereby enabling optical reading by the reader 6 from inside to outside of the core member 11. In this case, the light passing part is constituted by the through window 111 and the fitting member. In this configuration, the space of the through window 111 is filled with the fitting member, thereby allowing the outer surface of the fitting member and the outer surface of the core member 11 to be substantially flush with each other. Thereby, the occurrence of recesses in the portion of the packaging material 12 wound around the core member 11 corresponding to the through window 111 can be reduced.

Further, the through window 111 that is a through hole as in the embodiment is not necessarily provided in the core member 11. For example, the core member 11 can be formed by integrally molding a material through which light passes and a material that blocks light, so that a portion formed by the material through which light passes serves as a light passing part. Further, the entirety of the core member 11 can be formed by molding a material through which light passes, so that a part thereof, specifically, a portion that coincides with the reader 6 when the core member 11 is mounted on the holding unit 2 serves as a light passing part. In this case, portions other than the portion serving as the light passing part may be coated or uncoated.

The medicine packaging device may further include a printing unit configured to print information on medicine that is sealed within the packaging material 12 onto the packaging material 12. The medicine packaging device also uses an ink ribbon that is another sheet material than the packaging material 12 of the aforementioned embodiment. The printing unit serves as an action unit that performs an action of “printing” associated with the ink ribbon. In this case, the ink ribbon is wound around another core member than the core member 11 of the aforementioned embodiment, and another roll body than the roll body 1 of the aforementioned embodiment is formed. Then, an ink ribbon end detection mechanism is formed as a sheet material end detection mechanism.

Finally, the configuration and action of the aforementioned embodiment (including the modifications) will be summarized. The aforementioned embodiment is a packaging material end detection mechanism including: a roll body 1 constituted by winding a packaging material 12 around a tubular core member 11; a holding unit 2 configured to hold the roll body 1 so as to allow the packaging material 12 to be withdrawn; a packaging material information part 14 provided in the roll body 1 and indicating information on the packaging material 12; a reader 6 configured to optically read the packaging material information part 14 of the roll body 1 held by the holding unit 2; and a detection unit 8 configured to detect that the packaging material 12 is used up based on results of the reading by the reader 6, wherein the core member 11 has a light passing part (through window 111) through which light passes so as to enable the optical reading by the reader 6 from inside to outside, the roll body 1 has a seal 13 located between an outer surface of the core member 11 and an inner surface of the packaging material 12 and used for forming the packaging material information part 14, the packaging material information part 14 is formed in a portion of the seal 13 corresponding to the light passing part (through window 111), the seal 13 is attached to the core member 11 and the packaging material 12, adhesive force between the packaging material 12 and the seal 13 is larger than adhesive force between the core member 11 and the seal 13, and the detection unit 8 is configured to detect that the packaging material 12 is present when a read signal of the packaging material information part 14 read by the reader 6 is received and that the packaging material 12 is used up when the read signal disappears, during the withdrawing action to withdraw the packaging material 12 from the roll body 1 held by the holding unit 2.

According to the aforementioned configuration, the roll body 1 is constituted by winding the packaging material 12 around the tubular core member 11. The packaging material information part 14 indicating information on the packaging material 12 is formed in the roll body 1. The roll body 1 is held by the holding unit 2 so as to allow the packaging material 12 to be withdrawn. When the roll body 1 is held by the holding unit 2, the packaging material information part 14 of the roll body 1 is optically read by the reader 6. The core member 11 has a light passing part (through window 111) through which light passes so as to enable the optical reading by the reader 6 from inside to outside. The roll body 1 has the seal 13 located between the outer surface of the core member 11 and the inner surface of the packaging material 12 and used for forming the packaging material information part 14, and the packaging material information part 14 is formed in the portion of the seal 13 corresponding to the light passing part (the through window 111). Accordingly, the reader 6 can read the packaging material information part 14 until immediately before the packaging material 12 is used up. The seal 13 is attached to the core member 11 and the packaging material 12. Thus, since the seal 13 is attached also to the core member 11, the operation of aligning the light passing part (through window 111) of the core member 11 with the seal 13 can be facilitated. Moreover, since the adhesive force between the packaging material 12 and the seal 13 is larger than the adhesive force between the core member 11 and the seal 13, as the packaging material 12 is withdrawn from the roll body 1, the seal 13 on which the packaging material information part 14 is formed is finally taken away from the core member 11 together with the packaging material 12. Then, the packaging material information part 14 is displaced from the position corresponding to the light passing part (through window 111). Therefore, the reader 6 cannot read the packaging material information part 14 anymore. Based on this point, the detection unit 8 is configured to detect that the packaging material 12 is present when a read signal of the packaging material information part 14 read by the reader 6 is received and that the packaging material 12 is used up when the read signal disappears, during the withdrawing action to withdraw the packaging material 12 from the roll body 1 held by the holding unit 2. Thus, the detection unit 8 can detect that the packaging material 12 is used up by the fact that the reader 6 cannot read the information display. According to Patent Literature 1, the detection is performed using a mechanical configuration by the “paper end detection pin”, but the aforementioned configuration does not need to provide a mechanical configuration for detecting that the packaging material 12 is used up and can give a packaging material end detection mechanism in which malfunction is less likely to occur.

Further, the aforementioned embodiment is a roll body 1 including: a tubular core member 11; a packaging material 12 wound around the core member 11; and a seal 13 located between an outer surface of the core member 11 and an inner surface of the packaging material 12 and used for forming a packaging material information part 14 indicating information on the packaging material 12, wherein the core member 11 has a light passing part (through window 111) through which light passes so as to enable optical reading from inside to outside, the packaging material information part 14 is formed in a portion of the seal 13 corresponding to the light passing part (through window 111), the seal 13 is attached to the core member 11 and the packaging material 12, and adhesive force between the packaging material 12 and the seal 13 is larger than adhesive force between the core member 11 and the seal 13.

According to the aforementioned configuration, the roll body 1 is constituted by winding the packaging material 12 around the tubular core member 11. The roll body 1 includes the seal 13 used for forming the packaging material information part 14 indicating information on the packaging material 12. The core member 11 has a light passing part (through window 111) through which light passes so as to enable the optical reading from inside to outside. The seal 13 is located between the outer surface of the core member 11 and the inner surface of the packaging material 12, and the packaging material information part 14 is formed in the portion of the seal 13 corresponding to the light passing part (through window 111). Accordingly, the packaging material information part 14 can remain until immediately before the packaging material 12 is used up. The seal 13 is attached to the core member 11 and the packaging material 12. Thus, since the seal 13 is attached also to the core member 11, the operation of aligning the light passing part (through window 111) of the core member 11 with the seal 13 can be facilitated. Moreover, the adhesive force between the packaging material 12 and the seal 13 is larger than the adhesive force between the core member 11 and the seal 13. Therefore, as the packaging material 12 is withdrawn from the roll body 1, the seal 13 on which the packaging material information part 14 is formed is finally taken away from the core member 11 together with the packaging material 12. Then, the packaging material information part 14 is displaced from the position corresponding to the light passing part (through window 111). Accordingly, the packaging material information part 14 can be used also for detecting that the packaging material 12 is used up.

Further, the aforementioned embodiment is a method for producing a roll body by winding a packaging material 12 around a tubular core member 11, the core member 11 having a light passing part (through window 111) through which light passes so as to enable optical reading from inside to outside, the method including: a step of forming a packaging material information part 14 indicating information on the packaging material 12, on a seal 13 for forming the packaging material information part 14; a step of attaching the seal 13 onto an outer surface of the core member 11 so that the packaging material information part 14 corresponds to the light passing part (through window 111); a step of attaching the seal 13 to a winding start portion of the packaging material 12 with adhesive force larger than adhesive force between the core member 11 and the seal 13; and a step of winding the packaging material 12 around the core member 11.

According to the aforementioned configuration, the tubular core member 11 has the light passing part (through window 111) through which light passes so as to enable the optical reading from inside to outside. When producing the roll body 1, the packaging material information part 14 indicating information on the packaging material 12 to be wound around the core member 11 is first formed on the seal 13 used for forming the packaging material information part 14. Thereafter, the seal 13 is attached onto the outer surface of the core member 11 so that the packaging material information part 14 corresponds to the light passing part (through window 111). Accordingly, the operation of forming the packaging material information part 14 on the seal 13 and the operation of aligning the packaging material information part 14 with the light passing part (through window 111) can be facilitated. Further, the seal 13 is attached to the winding start portion of the packaging material 12 with adhesive force larger than the adhesive force between the core member 11 and the seal 13. Thereafter, the packaging material 12 is wound around the core member 11. Accordingly, the packaging material 12 can be temporarily fixed to the core member 11, and thus the packaging material 12 can be smoothly wound around the core member 11.

As described above, the aforementioned configuration can eliminate the need to provide a mechanical configuration for detecting the using up of the packaging material 12 and can give a packaging material end detection mechanism in which malfunction is less likely to occur. Therefore, it is possible to conveniently detect that the packaging material 12 is used up without using any mechanical configuration.

REFERENCE SIGNS LIST

-   1 Roll body -   11 Core member -   111 Light passing part, Through window -   112 Inner surface -   12 Sheet material, Packaging material -   13 Forming part, Seal -   14 Sheet material information part, Packaging material information     part -   2 Holding unit -   5 Action unit, Sealing unit -   6 Reader -   7 Control unit -   8 Detection unit 

1. A sheet material end detection mechanism comprising: a roll body constituted by winding a sheet material around a tubular core member; a holding unit configured to hold the roll body so as to allow the sheet material to be withdrawn; a sheet material information part provided in the roll body and indicating information on the sheet material; a reader configured to optically read the sheet material information part of the roll body held by the holding unit; and a detection unit configured to detect that the sheet material is used up based on results of the reading by the reader, wherein the core member has a light passing part through which light passes so as to enable the optical reading by the reader from inside to outside, the roll body has a forming part located between an outer surface of the core member and an inner surface of the sheet material and used for forming the sheet material information part, the sheet material information part is formed in a portion of the forming part corresponding to the light passing part, the forming part is attached to the core member and the sheet material, adhesive force between the sheet material and the forming part is larger than adhesive force between the core member and the forming part, and the detection unit is configured to detect that the sheet material is present when a read signal of the sheet material information part read by the reader is received and that the sheet material is used up when the read signal disappears, during the withdrawing action to withdraw the sheet material from the roll body held by the holding unit.
 2. A roll body comprising: a tubular core member; a sheet material wound around the core member; and a forming part located between an outer surface of the core member and an inner surface of the sheet material and used for forming a sheet material information part indicating information on the sheet material, wherein the core member has a light passing part through which light passes so as to enable optical reading from inside to outside, the sheet material information part is formed in a portion of the forming part corresponding to the light passing part, the forming part is attached to the core member and the sheet material, and adhesive force between the sheet material and the forming part is larger than adhesive force between the core member and the forming part.
 3. A method for producing a roll body by winding a sheet material around a tubular core member, the core member having a light passing part through which light passes so as to enable optical reading from inside to outside, the method comprising: a step of forming a sheet material information part indicating information on the sheet material, on a forming part used for forming the sheet material information part; a step of attaching the forming part onto an outer surface of the core member so that the sheet material information part corresponds to the light passing part; a step of attaching the forming part to a winding start portion of the sheet material with adhesive force larger than adhesive force between the core member and the forming part; and a step of winding the sheet material around the core member. 